The former ITV News presenter, 71, shared the news on Sunday (10 September) on GB News.
Appearing on The Camilla Tominey Show, Stewart, who retired earlier this year after almost five decades of being on TV, said: “I mean, the headline story, and it is relatively dramatic, I suppose, is that about six, nine months ago, I began to feel one of my favourite words, a bit discombobulated.
He said that that, after seeing his GP, he was sent for a scan that revealed he had had a series of “minor strokes that are called infarct strokes”. Stewart revealed that a diagnosis of vascular demantia followed.
Speaking about noticing early signs, he explained: “I wasn’t becoming forgetful but things like doing your shoelaces properly – that’s how I wear these lovely moccasins now – making sure your tie was straight, remembering that the call time for your programme is four o’clock and not five o’clock, not turning up early or late, and stuff like that.
“I then decided at my ripe old age of late 50s, early 60s, that I might have something wrong.”
According to the NHS, the common condition is caused by reduced blood flow to the brain, which has symptoms including slowness of thought and problems with concentration.
Stewart said that, following the news, he moved to “a contributor contract” at GB News and has appeared as a commentator on major news events such as the King’s Coronation for the channel.
He added: “The thing I have found most difficult to deal with, genuinely, is the impact it’s had on Sally, my wife. We’ve been married for nearly half a century, and, you know, your life partner, your lover, all of those descriptions that are personal and intimate, that person is reduced – I choose my words very carefully – almost to a carer.”
Stewart said his wife, who has worked as a production assistant, and with whom he has four children, had to make sure his “tie was done properly” before the interview.
He added: “So, if you do think that there’s something wrong with you, go and see the GP, listen to what he or she says. But also do remember that the people you work with and the people you live with and share your life with are the most important people in the entire world. And they are there if you’re lucky enough, as I was, to help you.”
Stewart left ITV in 2020, where he had presented a range of news and current affairs programmes including the evening news, lunchtime news and News At Ten, after more than 35 years with the broadcaster.
He hosted his final episode of Alastair Stewart And Friends, a discussion programme on GB News, in March.
During his career, Stewart has covered stories such as the Beslan school siege in Russia, the fall of the Berlin Wall in Germany, and various royal weddings.
He was named Presenter of the Year at the Royal Television Society Awards in 2004, and two years later was made an OBE for services to broadcasting and charity.
He started his career in 1976 at ITV’s Southern Television in Southampton, where he served as a general reporter, industrial correspondent, presenter and documentary-maker.
In 1980 he joined ITN as industrial correspondent and a decade later became Washington correspondent.
He went on to anchor ITN’s coverage of the first Gulf War and became the first UK TV reporter to broadcast live from the liberated Kuwait City.
Stewart has also chaired debates with political figures, including Gordon Brown, David Cameron and Nick Clegg ahead of the 2010 General Election for ITV, and for GB News when Rishi Sunak and Liz Truss were bidding for the Conservative Party leadership.
Phillips, 62, said in July that she hopes her involvement in clinical trials will be a step towards defeating Alzheimer’s, telling Daily Mirror: “I can’t just lie down and accept it.”
Additional reporting by Agencies